Process for the preparation of new cellulose esters.



as catalyst nletliylenefsulfiate 'whic fluid fo'rmnf the mixture ziillowsft-hc acct? KINZTETD STATES PATENT omic-E JosErz xomscu'mhrio mm; am-1mg, or ilYdfl l-Rflllcll, Assmuons To socm'zrn crmmmuc DES USIHES'DU :mcNEKAUcT. Gum-Ann, P. MONN ET Efl" CARTIER), F

= rams, "smmc a, n coni oimwm OE FsAucE.

Ho Drawing.

Tr) it may concern: f '7 Be it known that we, J Komscxmr, a

i THEUMAnN, a citizen of the Republic of l mum, and residing both at Lyon, Department of Rhone France (whose post-oilice acirlrci :s are, fol-"the first, 2 L Qu'ai Claude- Bcrnunl, Lyon, and, for the second, 5 Place I Puvis dc Chuvann'es'f, Lyon,) have invented.

mined except 'with' difficulty-.5 has been attempted :t-o replace the sulfuric acid by weakacids, QI-3.Cld or neutral Salts, but in is vary slow.

can be obt'ainedfor exnmple causing fuming sulfuric acid torcacQ'upon trioxyrncthylenc (see Delcpimz,' Compteglfiendus, l29, -pa'ge 831) This body allows 'a' rapid acetylation of the cellulose at. low temperature, while yielding remarkably viscous'sclut-ions of cellulosc acetate in the acetlc'acidformcd.

Example: 100 grains-of. cot-ton are brought intc contact with i. rhiz ture of-(310 vr zms of aceiic acid, f-Qgra-ms of acetic anhyiirld, and

gi'a.ms .of,methylcnesulfate M" C. The reaction is allowcd mi ke place and; gradually the cocoa forms with the acetic acid 11 fluid andv homogeneous mixture. Thc product of this rs react on 18 acctylated by adding 250 grain jof acetic anhydrid. The

luti'on to be obtained in an easy and regular If it is not-desired to utilizefihe product directly as a solution'o'f the acetate, the process is carried a step far ther'to precipit'utc the acetate from its solution. This can accomplished advantageously after the product is suliiniittcd to partial saponitum.

'i =2. cellulose acct-ates thus obtained have Application filed-:Scpiember 5,1914; Sc'rialNQBGOAfiQ. 1L

citi-Zeri'i of'the Republic of Switz'rland, and

mreseuce of: lhcsc substances the acctylation w av. The. cotton dissolves gradually and cr about one-0r two hours at 10 0 the acetylaticn iscmn-p'lcfc and the solution has become perfectly clear and very .viscous.

the prooerfiy giving" aolichts' very 'viscou SOIUIUQZIS which it IS impossible to obtain by Y already known- I By replacing the mic acid or homologuesof acetic anhydrjid,

the same way. Claims: r

of methylene sulfate.

2. Thdprocess 0f pray -ri lating cellulose with acetic siiih'y dridrin the presence of methylene sulfa'tp cellulose which consists iuv'firsl; treating ccl. ,lulose w th an orgiinic'ihcidaud methylenc sulfate, 1 and then jesteriiying the. cellulose "thus treated infirm present process (Elle-E618 em loyed 4 means of'anynof the product-s specification m Patent. fieicentefi-J iliy 18, J

iccic imiiydrid 5y; for

other new cellulose esters can-be obtained in Y 1. The process ofi'grepairing neweslier of.

cellulose, which c0fls1$s1in e erigin e1,-- l lulose Wltllgll acid anhydridfin thepresencc; can beestcrified I new "acetic esters of cellulose, which consistsinlaoety Y 3. .The process ofpre'paring new es tersbf csters of cellulose which-conslslis in first treating cellulose with *ucetic *sicid "and methylene sulfate, and theii xcctylating the.

ofsnmll quantifies of Q'nfzicidhnhydrid 'alid of rncthylcne .fs'ulfs 'i ge, and j'a-fter reaction esterifying the cellulose by'aildingthe ncces-,

s'ziry-quantities-of anhydrid.

6. The .processof preparinghew acetic" treating-cellulose with: jacctic j' icid in the presence df-ls'rnall quantities of acetic anhydrid anclf methylcne sulfate, z nda-ftier reacnccessaryquantitiesofacetic :inhydril. 7. The process f-preparing new aceticesters ofcellulose; "which consists in, first hydrid andof methylene sulfate, after reaction acetylating the cellulose by adding thencccssary quantities of acetic anhydr f and finallyprecipitating thc acetate of cellulose from its solution. 1 I

'8. The process of preparing new acetic.

tion vacetylaliing'zlghe cellulose b'y addingthe f treating cellulose with acetic ackl in the f presence of small quantities of acetic .a n-' esters of cellulose, which consists in first. treating cellulose with acetic acid in the.

presence of small quantities of acetic an hydrid and of methylene sulfate, after reaction acetylating the cellulose by adding the necessary quantities of acetic anhydrid, and finally partially saponifying the ace tate of cellulose and then precipitating the same from its solution.

9. The process. of preparing new esters of cellulose, which consists in treating one hundred'parts by weight of cellulose with -a mixture ,of sizbhundred and tenparts by weight of acetic acid, fifty parts by weight of acetic anhydrid, and ten parts by Weight of methylene sulfate having a temperature of 30 (1., and then after reaction esterifying the cellulose by adding two hundred and 15 fifty parts by weight of acetic anhydrid.

In testimony whereof we have signed our names to this specification, in the presence of two subscribing witnesses.

- JOSEPH KOET SCHET.

MAX THEUMANN. Witnesses: l 1

JOHN J. ERNs'rER, MARIN VACHON. 

